Glaucoma is an ocular disorder characterized by excessive intraocular pressure (IOP), which causes damage to the optic nerve and can lead to permanent loss of vision. It is estimated that over 2.2 million Americans have glaucoma but only half of those are aware of it. Glaucoma is the second leading cause of blindness in the world. Current methods for monitoring patients at risk for glaucoma involve intermittent measurements of IOP on an in-patient basis, based on applied pressure and deformation of the eyeball. There also exist devices which attempt to continuously monitor IOP, for example using a pressure sensor which is implanted in the aqueous chamber of the eye to directly measure IOP. Other methods utilize a strain gauge embedded in a contact lens to indirectly measure IOP. These prior methods are inconvenient, expensive and measure IOP via a pressure sensor on the surface based on the slight motion of a foreign, rigid surface that does not record unrestricted motion of the cornea or sclera.
It has been found that scleral strain correlates to, and provides additional information to, IOP. As such, it is desired to have systems and methods for measuring IOP and/or scleral strain in a non-invasive fashion.